Dustproof watchcase with nonbreakable crystal



Dec. 29, 1931. H. s'cHwoB ET Al.

DUSTPROOF WATCHGASYE WITH* NONBREAKABLE CRYSTAL Filed Mlc'h 24, 1927 Patented Dec. 29, 1931 UNITED s'lillprlas PATENroFrIcE HENRI scBwoB, or: NEW YORK, AND JoHN M. TRIPET, or` nnooxnYN, NEW Yonx, AssIeNons` To `manuel co. INC., or NEW Yoan, ruit.,k A conromiTIoNl or NEW Yonx nrrs'rrnoor wnrcncnsn WITH NoNnnimxABLncnYsrnL Y Application ma umh 24, i927. serial no. 17%,855.

Our invention relates to watch cases nerally but is morevparticularlydesigne -Y to produce a dust-proof case for use in ywrist watchesand is specifically adapted tofacilitate the use of a non-breakable crystal in such cases. y

By non-breakable crystals we mean, those, usually made of some easily moldable, slightly elastic, flexible," transparent material, such for instance as Celluloid, compounds of urea or similar 1 materials, although possibly` crystals ofthis character and of the desired shape for use in our invention might be made of some form of tough glass.

The difficulties heretofore frequently encountered with non-breakable crystals onthe market have comprised the liabilityof such crystals to get loose Vfrom the ordinary frame in which they have been set,partly on account of their flexibility and. partly on account of their liability to contract andfex and with the variations of temperature an moisture. Also, by reason of their substantially `flat form they have been liable to be easily pressed clown upon thehands of the watchand interere with its satisfactory operation.. Moreover, cases for use withl wristy watches pro-v vided with ordinary glass or special nonbreakable crystals have not! been as dustproof asis desirable in view of the exposure of suchwatches to dust and dirt. l TIthas been the experience of' the applicants that dust will enter the movement of a watch more .readily through the front-,or crystal portion of the casing thanelsewhere and it isv one of the primary purposes of this invention to minimize this, for the entrance of dust, moisture orfthe like into the watchimovement is obviouslywmost deleterious. We find that with oury invention we. can utilize as a seal, to carry thisfinventive thought into efecha crystal so formed that' it acts as a dnstpand moisture excluding element, though the specic form of crystal disclosed herein constitutes only one embodiment of the invention.

Generally s eaking, our inventionovercomes all 'of t ese dificulties'y byv employing a crystal having a fairly wide, downwardly extending border lange, perfectly combined @o with amain body frame containing therwatch movement which is provided with a. deep peripheral' groove substantially at right angles to the face of the watch into which said ange may lit, whereby an efficient dust-proof joint is secured'. Such, construction is principally feasible with .crystals of Celluloid or similarly easily moldable material although it mi ht` be otherwise produced.

he 'best form` of apparatus kat present known to us embodying our invention is illustrated in the accompanying sheet of drawings in which: Fig. 11is a perspective View body of the case. p

Fig. 2 isra perspective view of the preferred form of crystal.

Fig. 3 is a .perspective viewvof the pre'- ferred form of outer framewhich also serves asa link in the Wrist band.

of the main Fig. 4 is a vertical, central ysection ofthe assembled casing showing a watch movement therein, and

Fig. '5 isa perspective view` upon a smaller scale of 'a completed watch showing a wrist band attached thereto.,` v

Throughout the drawings like reference characters indicate like'parts. 1 represents generally a watch movement having the hands 2, and 3 is the main body of the cas,- ing rwhich is usually formed of va block of metal having the cavity 13-in which the movement lfmay be set with` its dial 18 extending over they face of such cavity. This viframe body 3 has the deep peripheral slot or groove 4 formed in it. 5 represents the crystal having the-flange V61 of considerable width extending at rightlangles tothe face 'of the'crystal andadapted to nest in the slot 4 as shown in Fig. 4. Preferablyv the face of the crystal is joined tothe flange 6 by some convenient form of bead 7 which raises the face of lthe crystal the ydesired distance abovel the` dial 18 so as toicauseit to clearthe hands 2- e 8 is the outer ramevwhich, in the caseof a wrist watch, is made with projecting ears 10 vto which any convenient form* of wrist band.

of other materials in separate sections connected together by any adjustable fastening (not shown) in the usual Way. The outer frame 8, whether made in the form of a link for wrist watches or otherwise, is provided with a continuous inwardly extending lip 9 which overhangs and engages the periphery of the crystal 5, preferably engaging the peripheral depression in the bead 7, as shown in Fig. 4.

14 represents the usual winding stem projecting from the watch movement through slots 12 in the body of the case, 12a in the crystal flange and 12b in the outer frame or link 8. Preferably a sleeve or washer of elastic material such as felt indicated at l5 in Fig. 5 may surround the stem 14 and fill the surrounding portions of the slots 12, 12a and 12b to prevent admission of dust through the annular space which might otherwise be left between the stem and portions of the case immediately surrounding it.

Any convenient and usual means may be employed for detachably securing the parts in the assembled position shown in Fig. 4, such for instance as the small shoulders or projections 16, 16 on the exterior of the body 3 of the case engaging corresponding slots or depressions 17, 17 in the inner surface of the slightly elastic outer frame 8.

In operating the invention the watch movement 1 is set in the cavity 13 of the main body of the frame 3, the dial 18 placed over it, and the hands 2 placed in position, the crystal 5 then placed over the dial with its flanges 6 extending to the bottom of slots 4 in the main body 3, and the outer frame 8 snapped down into position as shown in Fig. 4. In taking out the watch movement from the case, the above operations are performed in reverse order.

The advantage of our invention comprise the firmness with which the crystal is gripped in the assembled casing so that it cannot pos- "i sibly drop out or getloose; the perfect character of the dust-proof joint between crystal and case body produced by the cooperating action of the deep groove 4, in the case body. and the relatively wide flange 6 on the crystal; the insurance of sufficient clearance for the hands 2 secured by the bead 7 without correspondingly increasing the thickness of the casing proper, and the increased rigidity given to the crystal by the use of said circumferential bead. This latter quality is particularly important because of the general flexibility of the material out of which nonbreakable crystals are usually made.

While we have illustrated our invention as applied to a watch of rectangular shape .it

`i case type. Also various changes in the details of construction could be made without departing from the principle of our invention so long as the main feature of the engagement of a relatively wide flange on the crystal engaging the correspondingly deep slot in the casing is retained.

Having described our invention, we claim:

1. A watch case comprising, in combination, a main body having a cavity for the reception of a watch movement and provided with a relatively deep peripheral slot, a crystal provided with a depending flange adapted to enter, and extend substantially to the bottom of, said slot, and means for holding said parts in assembled relation.

2. The combination in claim 1 in which said flange extends continuously around the periphery of said crystal, and is arranged at substantially right angles to the face thereof.

3. The combination in claim 1 in which said crystal is formed of a flexible material and is provided with a peripheral bead whereby the face of the crystal is stiflened and a portion of it spaced away from the main body of the casing frame.

4. The combination in claim 1 in which said main casing body and crystal flange are provided with registering slots through `which the Winding stem of the watch may project.

5. In a dust-proof watch, a casing, a watch movement therein, and a crystal of boit-lil: form having a continuous, depending peripheral flange of relatively considerable width molded integrally with its face and eX- tending substantially at right angles thereto and'closely fitting around the sides of said casing to form a dust-proof joint therewith.

6. The combination found in claim 5 in 'which said ciystal has a substantially flat face provided with a peripherally arranged slightly reentrant portion adapted to hold the area of the face of said crystal thereby surrounded slightly above and away frein the upper surface of said watch movement.

7. The herein described dust-proof watch case having, in combination, a main body having a cavity for reception of a watch movement and a peripheral groove surrounding said cavity of substantially the saine depth as said cavity, a crystal shaped like a boX cover adapted to fit tightly into said groove, and a surrounding outer frame adapted to detachably engage said body and said crystal and hold the same in assembled relation with the crystal flange sunk in said groove.

8.v A watch having, in combination a cas ing, a movement therein, a winding stem and Y iid the parts are assembled, leave a small orifice through which said stem may roject.

9. In a Watch case the com ination of a main body adapted to receiveand hold a watch movement and provided on its face with an encircling marginal groove', the op? posite walls of which groove extend Vsub-f` stantially perpendicularly to the plane of the said face, a crystal provided with a continuous depending flange adapted to fit snugly in said groove when the parts are assembled, and means for holding said parts in assembled relation.

10. A watch having a dust-proof case comprising a back and sides, a watch movement therein, a watch crystal having its peripheral edge turned down and extending on a pluralityof its sides to approximately the depth of the casing sides and frictionally fitting the same, and a winding stem proj ectlng through said case. Y

11. As an element in a dust proof watch case embodying the construction herein` described, a watch case body in the form of a shallow receptacle adapted to receive and hold a watch movement and provided with a narrow, peripheral groove surrounding thc movement-holding space therein, said groove being of uniform width throughout and of a depth several times its width; whereby, when a crystal having a continuous, peripheral, right-angled flange adapted to fit snugly` in said groove hassuch flange nested therein,

a dust proof enclosure for the contained watch movement is thereby produced.

l2. In a watch, the combination of a watch crystal having a flange which is perpendicular with respect to a plane at right angles to the principal axis of the crystal around its i periphery and a watch case adapted to carry said crystal, in which the bezel of said case engages the front of said crystal and the depending flange extends into the case centre and around the Watch movement.

13. In a watch, the combination of a watch crystal having a flange which is perpendicular with respect to a plane at right angles to the principal axis of the crystal around its periphery, a step around the crystal face, and a watch case adapted to carry said crystal, in which the bezel of said case engages the front of said crystal andthe depending ange extends into the case centre and around the watch movement. f

14. In a watch, the combination of a watch crystal having a flange which is perpendicular with respect to a plane at right angles to the principal axis of the crystal around its periphery, and a watch case in which the bezel engages theffront of said crystal, and the back of said case engages the depending flange of the crystal to form a'joint between the casing and the crystal.

HENRI SCHWOB.

JOHN M. TRIPET. 

